Prophy is a statically typed, binary, tag-free, unpacked serialization protocol.

You can define message schema:

struct MyMsg
{
    u16 x<>;
};

generate codecs for chosen languages:

prophyc --python_out . --cpp_full_out . --cpp_out . test.prophy

and serialize data in Python:

>>> import test
>>> msg = test.MyMsg()
>>> msg.x[:] = [1, 2, 3]
>>> msg.encode('<')
'\x03\x00\x00\x00\x01\x00\x02\x00\x03\x00\x00\x00'
>>> print msg
x: 1
x: 2
x: 3

in C++:

#include <iostream>
#include <iterator>
#include "test.ppf.hpp"

int main()
{
    prophy::generated::MyMsg msg{{1, 2, 3}};
    std::vector<uint8_t> data = msg.encode();
    std::copy(data.begin(), data.end(), std::ostream_iterator<unsigned>(std::cout, " "));
    std::cout << '\n' << msg.print();
    return 0;
}

3 0 0 0 1 0 2 0 3 0 0 0
x: 1
x: 2
x: 3

again in C++ (half hand-rolled, compiler-dependent, but fastest option):

#include <iostream>
#include <iterator>
#include <cstdlib>
#include "test.pp.hpp"

int main()
{
    MyMsg* msg = static_cast<MyMsg*>(std::malloc(12));
    msg->num_of_x = 3;
    msg->x[0] = 1;
    msg->x[1] = 2;
    msg->x[2] = 3;
    std::copy((uint8_t*)msg, ((uint8_t*)msg) + 12, std::ostream_iterator<unsigned>(std::cout, " "));
    std::cout << '\n';
    return 0;
}

3 0 0 0 1 0 2 0 3 0 0 0

Documentation: http://prophy.readthedocs.org

Issues: https://github.com/aurzenligl/prophy/issues